To manufacture components, it is often necessary to rigidly interconnect two or more component parts. If the material of the component parts is suitable, the friction stir welding technique may in particular be used; in this process, component parts are positioned on a base plate without any overlap. By a rotating pin, enough frictional heat is then generated in a joint region for the components to fuse together at this point.
The method is particularly suitable for component parts that have a relatively low melting point and good thermal conductivity. In particular, the method is suitable for connecting components made of light metal, such as aluminium or aluminium alloys.
However, using the method to connect plastics components, for example thermoplastic components, is problematic, in particular owing to the low thermal conductivity thereof. In order to still cause the material in the joint region to melt, the friction stir welding tool (in particular the pin thereof) and/or thermoplastic parts to be joined are heated by a separate heat source.
For this purpose, induction heaters, infrared heaters, laser devices and/or heating plates or heating wires can be used.
However, incorporating additional heat sources of this type results in the method becoming more complex than a standard friction stir welding process. Furthermore, the additional heaters increase the complexity and the fault susceptibility of the machinery, and thus in particular increase the machinery and maintenance costs.